**5.2 Milk production**

Both semi-extensive and intensive farms are focused on milk production as the main economical resource. The main differences between the two opposite poles lie, in general, in the number of goats (small-medium farms in the most extensive systems, with 250–450 heads, and large intensive farms, with 700–1500 heads), and the reproductive system (from one kidding to three to four kidding seasons per year, respectively). Under this perspective, semi-extensive farms present periods of total absence of milk production; meanwhile intensive farms, with a planned reproductive schedule, are theoretically able to offer milk all year round. However, despite the intensification process of some farms, milk production continues to be seasonal, with maximum production in spring and minimum at the end of summer and beginning of autumn, which is opposite to milk prices, which are lower in spring and higher in autumn and early winter.

## **5.3 Intensive systems**

Most of the farms under this system can be considered as dairy farms. These farms follow a permanent housing of the animals, generally in communal yards that have uncovered areas. Feeding used to be indoors. Different paddocks keep animals in the same phase of lactation or with the same level of production.

The minimum number of heads is around 300, with a mean milk production of 400 liters per lactation. They have milking parlors, usually with electronic identification systems to record individual milk production.

From a reproductive point of view, these farmers are integrated in a breeders' association, under a genetic improvement plan, where artificial insemination with semen from the best bucks is usual.

Kids are like a by-product, and they contribute to around 20% of the income of the farm. Colostrum is provided by esophageal cannulas and kids are fed by automatic milk feeders.

### **5.4 Semi-extensive systems**

These farms are based on the production of kid meat, but goats are also milked for up to 5–7 months, so that they use dual-purpose breeds. Kids are reared by their mothers, and after weaning start manual or mechanical milking.

The reproductive calendar follows in general one kidding per year, although some farmers try to reach three kidding seasons in 2 years.

Traditionally, farms under this semi-extensive program are located in two different geographical areas: mountains and valleys. Goat farms in the mountainous areas have a higher number of heads (>100) and grazing in communal pastures. Animals receive an energy supplement at the end of pregnancy and during lactation. Milking used to be manual. Lowland farms are smaller (25–50 females), using in general by-products from the industry as a supplementary feeding to grazing [19–20].

### **5.5 Extensive systems**

Extensive farms are based on a natural land use, with a low amount of external income and with grazing as the main food resource for the animals. In general, farmers rear autochthonous breeds, well adapted to these areas [9].

The main goal of these farms is the production of young animals as described in Section 3.2. However, sometimes, very traditional farmers milk their goats for 1–2 months to manufacture small amounts of cheese.

This system includes small farms (150–200 goats), located in mountain areas, with limited/old facilities. Usually, housing is only overnight in rustic/old buildings. The flock is accompanied by the shepherd, with around 0.5–2 goats/ha.

The reproductive system is limited to one kidding per year.
